I have pb piping in my home built in late 1988. The outside line from meter to house was replaced about two years ago. Lately, I have had to remove screens, etc, from my faucets, shower head and other fixtures to remove small white granules that slow the flow. The granules will crush between my fingers with little effort sometimes....called water company, they advise that unless it's coming out of outside faucets (direct line from meter) it's an internal problem...I feel like it's chlorine coming thru the lines from processing plant.....have you ever heard of pb deteriorating from the inside and causing white particles to clob fixtures? Thanks.